This invention relates to a new and improved insert for shoes, particularly athletic shoes, and more specifically to an insert which spreads a user's weight over a wider area of the midsole, and is sufficiently variable in flexibility to impart greater user comfort when walking or running.
Numerous publications have dealt with inserts for running shoes, and some publications in this field include U.S. Pat. Nos. 3,999,558; 4,486,964; 4,654,984; 4,686,993; 4,800,657; 4,823,420; 4,888,888; 4,894,934; 4,905,383; 5,014,706; 5,311,680; 5,345,701; 5,353,523; 5,396,718; 5,400,528; 5,437,110; 5,513,448; 5,438,768; 5,488,786; 5,511,324; and, 5,528,842.
However, these patents do not provide inserts having the requirements of being sufficiently thin to produce a comfortable fit within the shoe while still imparting some cushioning properties, along with variable flexibility. This allows the user to change the midsole response of the shoe to user requirements.